1. Field of the Invention
The present invention generally relates to an image forming apparatus that is incorporated in a facsimile machine having no photocopy function, a facsimile machine having a photocopy function and the like, and more particularly to such image forming apparatus that is characterized by its paper selection.
2. Description of the Related Art
An image forming apparatus, which is represented by a facsimile machine having a photocopy function, selects a recording sheet from paper cassettes and prints image data on the selected sheet when making a photocopy or receiving image data from a remote machine. The image forming apparatus selects the sheet in accordance with the size of the image data on an original document or that of the received image data. If a so-called automatic rotation mode, which automatically turns the image data 90 degrees, is turned on, the image forming apparatus also considers the turned image when selecting the recording sheet. Specifically, if image data is printable on a sheet of paper as a result of turning, the image forming apparatus turns the image and prints it.
When the image forming apparatus can synthesize image data of one page with image data of another page and print the synthesized image on a single sheet of paper, i.e., when a page synthesis (or combine) mode is turned on, it does not use two sheets of paper; it combines two-page worth image data and prints it on a single sheet of paper.
Referring to FIG. 17A of the accompanying drawings, it should be assumed here that the image forming apparatus receives two pages of image data, and the length of the image data in each page is greater than the half of the letter size but smaller than the half of the legal size. If a first paper cassette holds sheets of legal size and a second paper cassette holds sheets of letter size, the image forming apparatus selects the second cassette and uses two sheets of letter-size paper to print the two-page worth image data. As a result, an approximate half of each of the letter-size paper is left as a margin (or a white area). This wastes the paper.
Referring to FIG. 17B, let's assume now that the image forming apparatus receives two-page-worth data, of which image data length in each page is shorter than the half letter size. If the first paper cassette holds the legal size paper and the second paper cassette holds the half letter size paper, the received images are combined and printed on a single sheet of legal size paper. Accordingly, a margin is left in the second half of the recording sheet (legal size paper). This also wastes the paper.